A storage device shared by a plurality of host servers stores data by allocating a specific region for each of the host servers. That is, the storage device stores data read or written by a host server and data received from another host server. In such a circumstance, to prevent the data from being destroyed or leaked by a malicious user, the storage device performs access restriction by granting access authority only to a specified user and restricting access from an unspecified user.
For example, with the use of iSCSI (Internet Small Computer System Interface) Name or World Wide Name uniquely determined for each host server (hereinafter referred to as the “host name”), the storage device identifies the host server which has accessed the storage device. Further, the storage device only accepts access from a host server, the host name of which has been registered, and rejects access from a host server, the host name of which has not been registered. Thereby, the storage device restricts access from an unspecified host server.
The identification of a host server by a storage device will be described with reference to a specific example. FIG. 13 is a diagram for explaining host identification by a storage device. The storage device illustrated in FIG. 13 has registered a host name “xxx1” of a host A as an access-permitted host. Further, the storage device is connected to the host A and a host B via a network, such as an IP (Internet Protocol) network or a SAN (Storage Area Network).
Further, if an access request is received from the host A, the storage device acquires the host name “xxx1” of the host A. The storage device determines that the acquired host name “xxx1” has been registered, and permits access from the host A.
Meanwhile, if an access request is received from the host B, the storage device acquires a host name “xxx2” of the host B. The storage device determines that the acquired host name “xxx2” has not been registered, and rejects access from the host B. As well as the method using the host name, a method of identifying a host server by using the MAC (Media Access Control) address or the IP address has also been used.
The above-described related art, however, has an issue of difficulty in preventing spoofing by a third party. Specifically, if the storage device is accessed by a third party having acquired a valid host name in some way, the storage device is incapable of distinguishing the third party from a valid host server.
In the example illustrated in FIG. 13, if an access request is received from the unregistered host B, the storage device rejects access on the ground that the host name “xxx2” for identifying the host B has not been registered. If the host B has acquired the host name of the host A in some way, however, the storage device determines the host B as the registered host A. Thus, the storage device permits access from the unauthorized host B. That is, if the storage device identifies a host on the basis of the host name, the storage device is incapable of preventing spoofing by a third party having acquired a registered host name in some way.